1. Field of the Invention
The present invention relates to a needle moving device for moving a needle to a designated position. Such a needle moving device is applied to an autosampler for moving a needle to a position of a designated sample vessel to carry out sampling or a fraction collector for moving a needle to a predetermined position to drop an eluting solution from a liquid chromatograph to the position.
In the following description, the “needle” includes not only a needle-shaped member to be inserted into the sample vessel to take in a solution but also a needle just for dropping a solution.
2. Description of the Related Art
An autosampler and a fraction collector are for moving a needle to a designated position to take in or drop the sample. A needle moving device for moving the needle to the designated position is formed to move the needle in two directions orthogonal to each other in a horizontal plane and a vertical direction, in general. The needle moving device has a mechanism for moving the needle in each direction by driving pulse motors, and the needle moves a distance according to a pulse signal provided to each pulse motor in each direction (see Patent Document 1, for example).
Driving of the needle is generally controlled by a system controller. A personal computer, for example, which allows inputting, outputting, and displaying of information, is connected to the system controller, and an operator can control operation of a device including the needle moving device through the personal computer.
In the following description, a device such as the autosampler and the fraction collector for actually moving the needle to perform sampling or dispensing is defined as a performing device. On the other hand, a device such as the system controller connected to the performing device to control operation of the performing device is defined as an arithmetic processing device.